At St. Damien Hospital, which is the only free pediatric hospital in the poverty-stricken Caribbean nation, injured children, and even some adults, have been pouring in since the quake hit Tuesday.
The Rev. Rick Frechette, hospital director, doctor and priest, welcomes them all, including one little girl whose face was badly burned. Her family had been preparing a meal when the quake hit.
"They made food, beans, and, then, after it was all cooked, they put it on the table," Frechette told ABC News senior health and medical editor Dr. Richard Besser. "But, then, during the earthquake it all fell, so it fell on the face of the child.
"We're a pediatric hospital. We are also dealing with adults coming here with severe crush injuries and open compounds and open fractures."
St. Damien has been sharing its medical supplies with other relief workers and facilities, and ran out of supplies Thursday night.
If more supplies don't arrive in Haiti soon, there will be a significant increase in the number of deaths, Frechette said.
Frechette, who is known as "Dr. Rick," is an American who has also worked with children in Mexico and Honduras as part of the nonprofit Nuestros Pequenos Hermanos International, Spanish for Our Little Brothers and Sisters. The desperate need for medical care he witnessed while working in Haiti inspired him to go to medical school in the 1990s.
He returned to Haiti to help build St. Damien and said that the hospital had been flooded with quake victims.
Other hospitals and relief workers in Haiti also report that they are overwhelmed by the number of victims and are desperate for additional support.
St. Damien is located outside Port-au-Prince and sees about 35,000 children each year. It averages a two-month stay, in a country where so many die from waterborne illnesses such as diarrhea and hepatitis A, as well as malnutrition and HIV.
Only about 50 percent of children in Haiti received vaccinations for diseases such as DPT (diphtheria, pertussis and tetanus), polio and measles in 2007, according to UNICEF. Haiti ranks 181st in the world in life expectancy.
Haiti has the highest per capita tuberculosis burden in the Latin American and Caribbean region, according to the U.S. Agency for International Development. After HIV/AIDS, TB is the country's greatest infectious cause of mortality.
Haiti is the poorest country in the Western Hemisphere and has "some of the worst health indicators in the world," Besser said earlier this week, and has a limited ability to absorb this kind of a catastrophe.
Medical aid would be one of the most important parts of the aid effort because Haiti's health care capacity was already limited before the quake, Besser said.
The United States has prepared the hospital ship the USS Comfort for possible deployment to the region.
"Access to quality care didn't exist before this earthquake," Besser said. "It doesn't exist now, so what's important is arranging evacuations and setting up hospitals. ... There's not a lot of time to save the most critically injured."